Chapter 8.9, Problem 2QC

Use the result of Example 2 to evaluate ${\displaystyle {\int }_1^{\infty }\frac{1}{x^4}}$ dx.

Example 2 The Family f(x) = 1/x^p

Consider the family of functions f(x) = 1/x^p, where p is a real number. For what values of p does ${\displaystyle {\int }_1^{\infty }f(x)}$ dx converge?